Viruses are parasitic, in that they require a host cell in order to go through the process of reproduction. when the influenza virus attaches itself to its host, which type of viral reproduction takes place?

Ihave no idea how to solve these. plus there's another question that is 2) a 10 kilogram meteorite is collected in space and brought back to earth. it is composed of 1.25 kg of uranium-238 and 8.75 kg of lead-206. how many u-238 half lives have passed? what is the approximate age of the meteorite?